ENERGY AND HEAT TRANSFER

​ENERGY AND HEAT TRANSFER

By Michael Adewumi

​What is Energy?

​Energy is the ability to do work or cause change.

• Energy is needed for movement, heating, lighting, and sound.

​Energy cannot be created or destroyed, only transferred

​What is Heat?

​Heat is a type of energy.

• Heat flows from hot objects to cold objects.

• Temperature tells us how hot or cold something is.

​Methods of Heat Transfer

​There are three ways heat energy can be transferred:

• Conduction

• Convection

• Radiation

​Conduction

​Conduction happens mainly in solids.

• Heat travels through particles by vibration.

• Metals are good conductors of heat.

​Convection

​Convection happens in liquids and gases.

• Warm fluids rise; cool fluids sink.

• This creates a convection current.

​Radiation

​Radiation transfers heat through waves.

• It does not need particles.

• Heat from the Sun reaches Earth by radiation.

​Everyday Examples

• Conduction: Frying pan heating food

• Convection: Hot air rising from a radiator

• Radiation: Feeling heat from a fire

​Plenary and Assessment

​Name one method of heat transfer.

• Give one example.

• True or False: Heat can travel through empty space.

​Frying pan on cooker

​Radiator warming a room

​Campfire giving off heat